<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<script type="text/javascript">
			//数值
			console.log(100)//十进制
			console.log(0xff)//16进制
			console.log(077)//8进制
			console.log(3.15159)
			console.log(3.5e3)
			
			console.log(typeof 100)
			console.log(typeof 3.145)
			
			console.log(1/0)//
			//字符串类型 string
			console.log('Hello World')
			console.log("hello world,"js"!")
			console.log(typeof "hello")
			
			//转义字符
			//\t 制表符
			//\r 回车符
			//\n 换行符
			//\''
			//\""
			//\\  \
			
			//布尔型
			console.log(true);
			console.log(false);
			var b=20;
			var a=10;
			console.log(a==b);
			console.log(typeof (a==b));
			
			//特殊类型
			//未定义
			var c;
			console.log(c);
			console.log(typeof c);
			
			//null 空值
			var d=document.getElementById("div01");
			console.log(d);
			console.log(typeof d);
			
		</script>
	</body>
</html>
